Abstract
In this paper, interesting transient phenomena that happen at the nozzle exit region are reported. When bubbles leave a nozzle, the bubbles form various complicated shapes. The processes of bubble generation from a nozzle were pictured using a high-speed video camera. In order to suppress unnecessary reflection at bubble surfaces, laser sheet illumination was polarized by a wire-grid filter. PTV measurement of flow adjacent to bubble surface were done simultaneously with observation of bubble surface by the present illumination system. As the result, local sudden acceleration and deceleration induced by complex deformation of a bubble can be measured.